Cartridge for guns



Nov. 5, 1946. J. o. EVANS, JR 0 3 CARTRIDGE FOR GUNS Filed June 5, 1942 awe/W600 John ELEvans, Jr.

Patented Nov. 5, 1946 UNETED? stares PATNT OFFICE "Washington, D. 0.

Application June 5, 1942, Seria lNo. 445,957

ioia'im. (01.102-38) "(Granted under the act of March 3, 1883, s

The invention described herein may be manufactured and used by or for tlieGovernment for governmental purposes, without the payment to invention relates to ordnance. Inone' of its aspects it relates to" a 'cartridge, particularly to a; small-arms cartridge; In another of its aspects it relates to a projectile for use in a A special gun.

mizes recoil because of a smoother acceleration of the projectile and, at the same time, permits extremely accurate engraving of the .projectile or its rotating band with concomitant high efficiency.

Another ob ect of the invention is to provide asimple cartridge embodying the principles of the invention which is adapted for use in conventional firearms.

Another object of the invention is to provide a projectile and gun combination employing separate loading ammunition and embodying the aforesaid principles.

Another object of the invention is to provide a separate loading projectile in accordance with the invention.

Still further objects and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a'fragmentary View, partly in section, of a cartridge in accordance with the invention positioned in the chamber of a rifle, and

Fig. 2 is a fragmentary View, partly in section, of a gun and projectile embodying the invention.

The invention involves in combination with an ordnance piece including a gun tube and a powder chamber receiving a propelling charge, a projectile seated in said ordnance piece, said projectile having a small first propulsion surface initially exposed to pressure generated by said charge and a second propulsion surface subsequently exposed to said pressure.

The cartridge embodiment of the invention includes a case providin a powder chamber receiving a propelling charge and having a neck portion providing a relatively small orifice and a projectile seated therein, said projectile having amended April 30, 1928; 370 O. G. 757) a first propulsion surface initially exposed' to pressure generated'by said charge and a second propulsion surface subsequently exposed ,to-said pressure. j

Referring now to Fig. 1, which shows' a cartridge in accordancewith the invention resting within the chamber of a riflei 4', 1 indicates a projectile having a head2 and a shank 3, The cartridge case 5, and also the exposed head 2 of the projectile, have conventional outside dimensions so that the cartridge is of proper size for conventional use. However, the neck 6 of the case is much thicker than the neck of the conventional cartridge, thus providing a relatively small cylindrical orifice 1 in which the cylindrical shank of the projectile is seated with a sliding gas-tight fit. The shank may have a slight forward taper, i. e., it diminishes in size from rear to front, so as to maintain the joint at the orifice gas-tight as the projectile moves forward after firing and, also, to retain the bullet in the case during shipment and handling. The case may also be thickened at the shoulder 8 for reinforcement against rupture at this point.

The projectile is provided with two separate and distinct propulsion surfaces against which the propelling gases generated by the propelling charge act to accelerate the projectile. The primary, or first propulsion surface, is the base 9 of the shank and the secondary propulsion surface is the rearwardly facing area I!) at the base of the projectiles head.

When the piece is fired, gases are rapidly generated by the propellant ll. These gases initially drive the projectile forward by action only upon the relatively small propulsion surface 9.

The acceleration takes place relatively slowly due to the small area upon which the gases are eifective.. When the projectile has advanced in the bore of the rifle a distance equal to the length of the shank, the base 9 of the shank clears the forward end of the orifice 1 thereby giving the gases within the cartridge case egress to the bore of the rifle where they are free to act, not only upon the primary propulsion surface 9, but also, in addition, upon the secondary propulsion surface lB. The accelerating force is thus considerably multiplied and the projectile is rapidly accelerated to the desired velocity.

The principles of the invention as applied to a large gun using separate loading ammunition will be explained with referenceto Fig. 2 of the drawing. The projectile la is provided with a. head 2a, and a shank 3a. The guntube 4a provides the powder chamber to. A collar 6a is provided for the projectile and is analogous to the thickened neck portion 6 of the cartridge case of Fig. 1. A gas-tight sliding joint is provided between the orifice 1a of the collar and the shank of the projectile. The collar and projectile preferably are loaded into the gun as a unit. A gastight jointitla is p'rovided between the collar and the wallsof the powder chamber. The primary propulsion surface is the base 9a of the shank and the secondary propulsion surface is the rearwardly exposed area Ilia at the base of the head. The powder charge Ila is separately loaded into the chamber.

The action of the propelling gases on the projectile in the modification of Fig. 2 is similar to the accelerating action as described in connection with Fig. 1, the propelling gases acting first on the base of the shank and subsequently additionally on the rearwardly facing base of the head.

After firing the gun, it will be necessary to remove the collar 61: before reloading, V

The relative size of shank and head of the projectile are not critical and may be varied within desired limits. The length of the shank may bevaried to give a longer or shorter delay to the full accelerating action of the propelling gases, and the relative areas of the primary and secondary propulsion surfaces may be varied, as the case requires, to regulate the initial acceleration. In general, however, the area of the primary propulsion surface will be distinctly smaller than the area of the total propulsion surface, being preferably less than three quarters thereof.

The term propulsion surface is intended to means a surface of the projectile upon which propelling gases are eifective for acceleration of the projectile. The area of such a surface will be considered to be the rectilinear projection of said area upon a plane perpendicular to the major axis of the projectile.

I claim:

A cartridge comprising an elongated case providing a powder chamber receiving a propelling charge and having a neck portion at one end, said neck portion having thick walls providing a substantially cylindrical orifice, a projectile having a forwardly tapered shank portion extending inwardly through the said orifice of said case, making a sliding gas-tight joint with the inner surface of said orifice and providing a primary propulsion surface at the end of said shank, said projectile having a head portion providing a sec,- ondary propulsion surface, the outside diameter of the head of said projectile being not greater than the outside diameter of the neck portion of said case.

JOHN O. EVANS, JR. 

